When a truck, trailer or some other vehicle is parked at a loading dock, often a vehicle restraint is used to keep the truck from inadvertently moving away relative to an elevated platform of the dock. This allows a forklift truck to safely drive between the dock platform and the truck for the purpose of loading or unloading the cargo inside the truck.
There are different vehicle restraints available that can be installed at a loading dock for engaging the truck's RIG (Rear Impact Guard), also known as an ICC bar. An ICC bar is a beam that extends horizontally across the rear of a truck, just below the truck bed. Its primary purpose is to prevent an automobile from under-riding the truck in a rear-end collision. However, not all trucks have an ICC bar that can be readily engaged by an ICC-style restraint. Moreover, ICC bars are not prevalent outside the United States, so in those cases, often a wheel chock is used for blocking one or more of the truck's wheels. Although wheel chocks and conventional ICC-style restraints are useful in certain applications, they do have their limitations.